Pool for performing physical activity in counter-current regime

ABSTRACT

A tank (1, 100) configured to carry out physical activity in a counter-current regime comprises a swimming section (2, 102), at least one propulsion section (3, 103, 103′) along which a fluid is forced, at least a first section connecting section (4, 104) and at least a second connecting section (5, 105) for the connection of respective ends of the swimming section (2, 102) and of the propulsion section (3, 103, 103′) at least one long fluid propulsion loop path, wherein the at least one first connecting section (4, 104) comprises a plurality of first curved channels and the at least one second connecting section (5, 105) comprises a plurality of second curved channels and wherein the platform (8, 108) is movable.

The present invention relates to a tank configured to generate a flow ofwater inside it to perform physical activity in so-called“counter-current” conditions.

Nowadays, the use of tanks or pools for swimming or more generallytraining in so-called “counter-current” conditions, that is, wherein auser is hit by a moving fluid against which to oppose, for example bywalking or swimming, is widespread.

The counter-current tanks allow physical activity to be carried out in alimited space compared to that necessary otherwise in a traditional typetank.

In general, a counter-current tank is configured to generate andmaintain in circulation a flow of water along a ring path through theuse of propulsion elements, such as a propeller immersed in water thatcan be rotated by a motor.

The tank has sections in succession to each other and in mutual fluidcommunication, configured to guide the flow of water along a propulsionsection, wherein the propulsion members are present, up to a usesection, accessible to a user, into which the water flow is introduced.

The propulsion section and the use section are mutually connected bymeans of elbow fittings, to form a closed loop or substantially ringpath, by means of suitable connecting sections.

U.S. Pat. Nos. 2,035,835 and 5,005,228 describe some examples of tanksfor counter-current swimming.

The counter-current tanks of the known art suffer from some drawbackswith reference, in particular, to the presence of turbulence of the flowalong the use section or, again, to the pressure drops along the looppath.

These turbulences do not allow the correct execution of physicalactivity, as the user not only finds himself having to counter thecurrent that hits him but must necessarily continue to compensate hisown arrangement to face the turbulence of the flow.

In addition, the head losses reduce the overall efficiency of the tank,understood as the ability to generate a ring flow and keep it constantduring the use of the tank itself.

As is well known, in fact, a turbulent flow has a chaotic course,whirling without follow ordered trajectories as in the case of a laminarfluid.

Keeping the flow motion constant and uniform along the section of use isnecessary to provide ideal conditions of use for a user. In practice, atthe use section, the motion of the fluid must be maintained in a laminarregime or as close as possible to the laminar regime to generate auniform current.

The difficulty of generating a laminar motion and keeping it constantalong the section of use is more noticeable in the tanks that have smalldimensions, since the perturbations due to the connection sectionsbetween the use section and the propulsion section occur with greaterintensity.

The solutions of the prior art do not allow to guarantee a laminarmotion of the flow along the section of use with reference in particularto small tanks, which can be installed in boats or for use in closedenvironments such as gyms or similar or, again, which can be installedin domestic environments.

The object of the present invention is to provide in a simple andefficient way a tank configured to force a water flow inside it along atleast one loop path, to allow the execution of physical activity incounter-current conditions, that is to say in contrast to a current ofwater that at least partially hits a user inside the tank.

A further object of the present invention is to allow a safe use of thetub as well as to make it safe during the period of non-use.

Another purpose of the present invention is to provide a tank configuredto perform counter-current physical activity of optimized dimensions, aspart of a solution with reduced overall dimensions compared to those ofthe prior art solutions.

A further object of the present invention is to provide a tank that canbe used for carrying out different activities in counter-currentconditions and, for this purpose, configured to house any equipmentnecessary for performing specific counter-current activity.

A specific object of the present invention is a tank configured toperform physical activity in a counter-current regime comprising aswimming section, a propulsion section along which a fluid is forced,wherein the swimming section and the at least one propulsion sectionextend along a longitudinal direction, at least a first connectingsection and at least a second connecting section for the connection, influid communication, of respective ends of the swimming section and ofthe propulsion section so as to define at least one ring path alongwhich the fluid, a platform interposed between the at least one firstconnecting section and the at least one second connecting section,wherein the at least one first connecting section comprises a pluralityof first curved channels, the at least one second connecting sectioncomprises a plurality of second curved channels, wherein the platformcan be movable between an intermediate lowered position, wherein isdistal from an access opening to the swimming section and a raisedposition wherein it hermetically closes the opening preventing access tothe swimming section, wherein the platform is optionally movable in alowered position, in abutment or substantially in abutment against abottom portion of the tank to act as a support surface.

According to another aspect of the invention, the at least one firstconnecting section can comprise a plurality of first curved channelswith an increasing section starting from the at least one propulsionsection towards the swimming section and wherein the at least one secondsection of connection can comprise a plurality of second curved channelswith a decreasing section starting from the swimming section to the atleast one propulsion section.

According to a further aspect of the present invention, the at least onefirst connecting section can comprise a plurality of first curved wallsshaped like a “C” or “U” placed one inside the other, mutuallydecentralized and with the respective concavities facing towards theswimming section and the at least one propulsion section.

According to an additional aspect of the present invention, the at leastone second connecting section can comprise a plurality of second curvedwalls shaped like a “C” or “U”, arranged one inside the other, mutuallydecentralized and with their respective concavities facing the swimmingsection and the at least one propulsion section.

According to another aspect of the present invention, the tank cancomprise at least a first deflector arranged at the at least one firstconnecting section and a second deflector located at the at least onesecond connecting section, wherein the first deflector and the seconddeflector are configured to reduce turbulence or detachment phenomenonof the flow at the end of the platform.

According to a further aspect of the present invention, the tank cancomprise propulsion members configured to impart a momentum to a fluidincluded in the tank, wherein the propulsion members comprise at leastone propeller operatively connected to a motor for its rotation drive,wherein the at least one propeller is arranged along the at least onesecond connecting section, below the platform.

According to an additional aspect of the present invention, the platformwhen placed in the intermediate lowered position can define a separationdiaphragm between the swim section and the propulsion section, keepingseparate a flow which is forced along the swimming section and a flowwhich is forced along the propulsion section in counter-current withrespect to the flow along the swimming section.

According to another aspect of the present invention, the firstdeflector can be arranged along the at least one first connectingsection, inside a cavity delimited by a first internal curved wallincluded in the at least one first connecting section, and the seconddeflector can be placed along the at least one second connecting sectioninside a cavity delimited by a second internal curved wall comprised inthe at least one second connecting section.

According to a further aspect of the present invention, the firstdeflector can be connected to the first grid and the second deflectorcan be connected to the second grid.

According to an additional aspect of the present invention, the firstdeflector has a cross section with a decreasing path along thelongitudinal direction with a direction starting from the at least onefirst connecting portion towards the swimming section.

According to another aspect of the present invention, the firstdeflector has a cross section configured as an ogive or drop element ora hydrodynamic element equipped with a rounded end placed inside thefirst internal curved wall, followed by it along the longitudinaldirection with the direction of flow advancement, a descending portionthat connects to the platform.

According to a further aspect of the present invention, the platform,the first deflector and the second deflector are mutually connected todefine a single body comprised along the swimming section, movablebetween the lowered position and the raised position.

The advantages offered by the tank according to the invention areevident.

In particular, the tank according to the invention allows to generate alaminar flow inside it as part of a solution with optimized overalldimensions.

The tank according to the present invention also includes a section ofuse, i.e. the section along which a user can access, which has largedimensions compared to the overall dimensions of the tank itself.

Furthermore, the tank according to the present invention is configuredto ensure high safety not only during its operation but also duringinactivity periods.

The present invention will now be described, for illustrative but notlimitative purposes, according to its preferred embodiments, withparticular reference to the Figures of the attached drawings, wherein:

FIG. 1 shows a schematic perspective view of a tank according to theinvention in an operational configuration;

FIG. 2 shows a perspective view from above of a tank according to theinvention;

FIG. 3 shows a sectional side view of the tank according to theinvention, in a further operational configuration;

FIG. 4 shows a perspective view from above of the tank of FIG. 3 ;

FIG. 5 shows a top view of the tank of FIG. 1 ;

FIG. 6 shows a perspective view from above of a further embodiment ofthe tank according to the invention;

FIG. 7 shows a top view of the tank of FIG. 6 ;

FIG. 8 shows a side sectional view of the tank of FIG. 7 ;

FIGS. 9 and 10 shows further components of the tank according to theinvention;

FIG. 11 shows a further version of the tank according to the presentinvention;

FIG. 12 shows some possible uses of the tank according to the presentinvention.

With reference to the attached Figures, it should be noted that the tankaccording to the invention is configured to generate and maintain a flowof water inside it, along at least a loop or substantially loop path.

With reference to FIGS. 1 to 5 , an embodiment of the tank according tothe invention is illustrated, indicated as a whole with the referencenumber 1.

The tank 1 comprises a use section or swimming section 2, inside whichit is possible to carry out a physical activity in counter-current, apropulsion section 3, along which the fluid is forced, at least a firstconnecting section 4 and at least a second connecting section 5 for theconnection, in fluid communication, of respective ends of the swimmingsection 2 and of the propulsion section 3 so as to define at least oneloop path along which to push a fluid.

The tank 1, at a top portion, defines an opening 6 for accessing the useor swimming section 2 of the same tank 1 (see, for example, FIGS. 1 and2 ).

In particular, the use or swimming section 2 and the propulsion section3 are positioned one above the other or, in other words, the swimmingsection 2 starts from a top portion of the tank 1, while the propulsion3 starts from a portion of the bottom of the tank 1.

In the following description reference will be made to a physicalactivity such as swimming, although it is understood that the tank 1 canalso be used for the execution of a different physical activity, such aswalking or pedaling or further counter-current exercises without anylimitation (see FIG. 12 illustrates equipment for carrying outactivities such as hydrorunning, platform 32 or hydrobike, bicycle 33).

The swimming section 2 and the propulsion section 3 extend along alongitudinal direction 7 of the tank 1 (see, for example, FIG. 1 ).

Preferably, the swimming section 2 and the propulsion section 3 have alinear development.

The swimming section 2 is separated from the propulsion section 3 by aplatform 8, which acts as a support base along the swimming section 2itself.

The platform 8 is interposed between the at least one first connectingsection 4 and the at least one second connecting section 5 (see forexample FIG. 1 ).

The platform 8, moreover, is configured to act as a mobile diaphragm todivide two counter-current flows present along respective sections ofthe tank 1, i.e. the flow of water along the swimming section 2 and thatpresent along the propulsion section 3 The mobility of the platform 8allows the tub 1 to assume different operating configurations, as betterdescribed below.

The at least one first connecting section 4 is configured to cause aninversion of the direction of advance of the fluid between thepropulsion section 3 and the swimming section 2. In this regard, itshould be noted that the at least one first connecting section 4comprises a plurality of partitions or curved walls shaped like a “C” or“U” or similarly, arranged one inside the other, mutually spaced anddecentralized and with their respective concavities facing the swimmingsection 2 and the propulsion 3.

With reference to what is illustrated in the attached Figures, the atleast one first connecting section 4 includes four first curved walls 9,10, 11 and 12 with increasing size starting from a first internal curvedwall 9 towards a first external curved wall 12.

The first curved walls 9, 10, 11, 12 delimit inside at least a firstconnecting section 4 of the first curved channels for the passage,inside them, of respective water flows. Each first curved channel has arespective inlet section, interposed between the at least one firstconnecting section 4 and the propulsion section 3, and a respectiveoutlet section, interposed between the at least one first connectingsection 4 and the section swimming 2.

It should be noted that for each first curved channel, the inlet sectionhas a smaller width than that of the respective outlet section. Inpractice, each first curved channel has an increasing variable sectionstarting from the inlet section towards the respective outlet section(see FIGS. 1 and 3 ). In other words, each first curved channel has anincreasing section along the direction of flow within at least one firstconnecting section 4, starting from the propulsion section 3 towards theswimming section 2.

The term amplitude refers to the area of the cross section with respectto the direction of advancement of the fluid within the first curvedchannels.

The at least one first connecting section 4 allows to divert and conveythe flow coming from the propulsion section 3 towards the swimmingsection 2, in order to limit the turbulence present in the flowoutcoming from the propulsion section 3.

The at least one second connecting section 5 has a similar conformationto that described in relation to the at least one first connectingsection 4.

In particular, the at least one second connecting section 5 isconfigured to cause an inversion of the direction of advancement of thefluid between the swimming section 2 and the propulsion section 3 andcomprises a plurality of curved walls or walls shaped like a “C” or “U”shaped one inside the other, mutually spaced, with the respectiveconcavities facing towards the swimming section 2 and the propulsionsection 3 and, therefore, opposed to the concavities delimited along theat least one first connecting section 4.

With reference to what is illustrated in the attached Figures, the atleast one second connecting section 5 includes four second curved walls13, 14, 15, 16 with an increasing size starting from a second internalcurved wall 13 towards a second external curved wall 16.

The second curved walls 13, 14, 15, 16 delimit inside the at least onesecond connecting section 5 of the second curved channels for thepassage of respective water flows, each of which has a respective inletsection, interposed between the swimming section 2 and the at least onesecond connecting section 5 and a respective outlet section, interposedbetween the at least one second connecting section 5 and the propulsionsection 3.

It should be noted that for each second curved channel, the inletsection has a greater amplitude than that of the respective outletsection.

In practice, each second curved channel has a decreasing variablesection starting from the inlet section towards the respective outletsection (see FIGS. 1 and 3 ) or, in other words, along the direction ofthe flow inside the tank 1, starting from the swimming section 2 towardsthe propulsion section 3.

In the attached FIGS. 1-5 the at least one first connecting section 4and the at least one second connecting section 5 each comprise fourbaffles or curved walls, although it is understood that further versionsare possible comprising a different number of curved walls according tospecifications requirements, for example as a function of the dimensionsof the at least one first connecting section 4 or of the at least onesecond connecting section 5 (or more generally of the tank 1).

The tank 1 comprises propulsion members configured to impart a momentumto a fluid comprised in the tank 1, pushing it along at least one closedpath, preferably in a loop.

According to a preferred embodiment, the propulsion members comprise atleast one propulsive propeller 17 operatively connected to a respectivemotor 18 for its rotation drive (see FIG. 1 wherein two propellers areshown schematically represented as two cylindrical bodies or FIG. 3wherein a schematic sectional view of a propeller is shown).

Preferably, the tank 1 comprises two propellers 17 arranged along adirection transverse to the direction of advance of the flow. It isunderstood that the total number of propulsive propellers 17 can varyaccording to the dimensions of the tank 1.

The propulsion members are arranged at the propulsion section 3 or alongit, according to specific use requirements.

Preferably, the propulsion members are positioned outside the plan areaof the swimming section 2. In particular, the propulsion members arearranged outside the plan encumbrance of the platform 8, so as not tointerfere with the movement of the itself.

The tank 1 comprises a first grid 19, interposed between the at leastone first connecting section 4, the swimming section 2 and a second grid20 interposed between the swimming section 2 and at least one secondconnecting section 5.

The first grate 19 and the second grate 20 are provided respectively touniform the flow entering the swimming section 2 and that leaving it.Furthermore, the second grid 20 prevents a user from being sucked intothe at least one second connecting section 5, in favour of safeoperation of the tank 1.

The tank 1 comprises a first deflector 21 and at least a seconddeflector 22 arranged at respective end portions of the platform 8.

According to the embodiment illustrated in the attached FIGS. 1 to 5 ,the first deflector 21 is arranged along the at least one firstconnecting section 4, inside the cavity delimited by the first internalcurved wall 7, while the second deflector 22 is arranged along the atleast one second connecting section 5, inside the cavity delimited bythe second internal curved wall 13.

More in detail, the first deflector 21 is connected to the first grid 19and therefore kept in position inside the first internal curved wall 9.

Similarly, the second deflector 22 is connected to the second grid 20and kept firmly in position within the second internal curved wall 13.

The first deflector 21 and the second deflector 22 are configured touniform flow, reducing turbulence, at the internal portion respectivelyof the at least one first curved section 4 and of the at least onesecond curved section 5.

The first deflector 21 has a cross section with a decreasing path alongthe direction 7, with a direction starting from the at least one firstconnecting section 4 towards the swimming section 2, so as to reduceturbulence and pressure drops at one end of the platform 8 close to theat least one first connecting section 4.

According to a preferred embodiment, the first deflector 21 has a crosssection configured as an ogive or drop element or, more generally, ahydrodynamic element provided with a rounded end, in particular the endwhich is arranged inside the first internal curved wall 9, followed by,along the flow forward direction, a descending, ramp portion, which isconnected, at the opposite end, to the platform 8.

This conformation allows to avoid a detachment of the flow at theinitial end of the platform 8, in order to reduce turbulence at theinternal curved wall 9 or to avoid cavitation phenomena.

The second deflector 22 has a proximal end to the second roundedinternal curved shaped wall 13, to favor the deviation of the flow alongthe at least one second connecting section 5.

According to an alternative embodiment illustrated by way of example inthe attached FIG. 11 , the propulsion members comprise one or morecentrifugal pumps, schematically indicated with 30, which suck waterfrom the tank 1, taking it from the at least one second connectingsection 5 and delivering it under pressure at the propulsion section 3,through suitably oriented nozzles, provided with Venturi tubes 31 toincrease the flow rate.

The platform 8 is mobile between a lowered, intermediate loweredposition, wherein it is distal from the opening 6 and arranged at a baseportion of the tank 1 (see FIGS. 1 and 2 ) and a raised position,wherein it acts as a sealing the opening 6 (see FIGS. 3, 4 and 11 . Inparticular, in the attached FIG. 11 , the platform 8 is shown in theraised position with solid lines and in the lowered position with dashedlines).

The platform 8 placed in the intermediate lowered position acts as aseparation element, or rather acts as a separation diaphragm, betweenthe swimming section 2 and the propulsion section 3, delimiting theswimming section 2 below and guaranteeing a support for a user insidethe latter.

With the platform 8 arranged in the completely lowered or substantiallycompletely lowered position, on the other hand, the tank 1 can be usedto perform activities such as water aerobics, hydrospinning,hydrorunning or the like (see FIG. 12 ).

The platform 8 arranged in the raised position provides a closingelement for the tank 1, preventing access to the swimming section 2. Inthis regard, along the top portion of the tank 1, at the perimeter ofthe opening 6, are provided sealing elements which are configured toselectively abut against the edges of the platform 8 and thus guaranteethe sealing of the closure which can be obtained by means of theplatform 8 itself.

Selectively closing the access to the swimming section 2 of the tank 1allows the safe use of the tank 1 itself, for example in boats, toprevent the use of the tank 1 or, more generally, to prevent access andprevent a user may accidentally fall into tank 1. Not only that, theplatform 8, arranged in the raised position, can be walked on so that,when not in use, it does not limit the space available in theenvironment wherein the tank 1 is installed, for example a gym of acruise ship.

Furthermore, with the platform 8 placed in the raised position tohermetically close the opening 6, the water from escaping from the tank1 is prevented, for example following the movement of the boat whereinthe tank 1 is installed. Furthermore, with the platform 8 in the raisedposition to hermetically close the opening 6, the accidental entry ofwater into the tank 1 itself is prevented, for example if the tank 1 isinstalled on a covered deck subject to flooding, to the advantage ofsafety of use of the tank 1 itself.

It should be noted that, with reference to the embodiment illustrated inthe attached FIGS. 1-5 , the first deflector 21 and the second deflector22 can each comprise a respective shaped portion configured to meet, bymeans of shape coupling, with respective end portions of the platform 8(see for example FIG. 3 ).

By way of non-limiting example, the first deflector 21 can comprise anabutment portion which extends along the longitudinal developmentdirection 7, inside the swimming section 2, and defines an abutment or asealing lip which can be housed, by coupling shape, in a respective seatprovided at one end of the platform 8. Similarly, the second deflector22 can comprise a respective abutment portion which extends along thelongitudinal development direction 7, inside the swimming section 2 anddefines an abutment or a sealing lip which can be housed by means of ashape coupling in a respective seat made at one end of the platform 8opposite to that which can be connected to the first deflector 21 (seeFIG. 3 ).

This shape connection between the first deflector 21 and the platform 8,as well as between the second deflector 22 and the platform 8, allows toobtain a sealed connection between the first deflector 21 itself, thesecond deflector 22 and the platform 8. As a fact, with the platform 8in the lowered position, a tight barrier between the swimming section 2and the propulsion section 3 is guaranteed, avoiding the generation offluid leaks and, consequently, turbulence at the connection portionsbetween both the first deflector 21, the second deflector 22 and theplatform 8.

In the tank 1 according to the invention, the presence of a mobileplatform 8, together with the presence of a first grid 19 and a secondgrid 20 provides an additional safety element in the use of the tub 1itself.

The tank 1 comprises movement members configured to selectively move theplatform 8 between the lowered and raised positions and intermediatepositions.

In the attached FIGS. 1 to 5 , the moving parts have been purposelyomitted in order not to interfere with the intelligibility of the same,while they have been illustrated through discontinuous lines in theattached FIGS. 9 and 10 .

The movement members comprise at least one motor unit 23 operativelyconnected to the platform 8 by means of motion transmission members andguide members configured to guide the platform 8 during its movement.

By way of non-limiting example, the motor unit 23 can be installedcentrally along the platform 8, below it, and the motion transmissionmembers can comprise a first transmission shaft 24 and a secondtransmission shaft 25 which are mirror-like to each other with respectto the motor unit 23 and connected to a power output of the latter bymeans of a transmission joint.

In turn, the first transmission shaft 24 is connected, by means of agearing 26, to a first axle 27 located at one end of the platform 8, andthe second transmission shaft 25 is connected, by means of a respectivegearing 28, to a second axle 29 located at the opposite end of theplatform 8 (see FIG. 11 ).

The first axle 27 is configured to engage respective first racks(schematically illustrated in FIG. 9 by means of dashed lines), meshingwith them by means of pinions. The first racks act as guide members formoving the platform 8.

Similarly, the second axle 29 is configured to engage respective secondracks (see FIG. 9) at the opposite ends, distal from the gearing,engaging them by means of pinions. The second racks act as guide membersfor moving the platform 8 along the swimming section 2.

It should be noted that the movement members described above allow toobtain a smooth movement of the platform 8, preventing it from tilting,jamming, during the movement between the lowered and raised positions,and vice versa.

According to alternative embodiments, not shown in the attached figures,the moving members of the platform 8 can be configured in a differentway and include, for example, motion transmission members provided withropes and return pulleys operatively connected to a motor unit and tothe platform 8, to obtain the movement of the latter along a guidebetween a lowered position and a raised position following the actuationof the motor unit itself.

As mentioned, the moving members, and in particular the motor unit 23,are arranged below the platform 8, so as not to clutter up the swimmingsection 2. Optionally, the moving members can be installed within thethickness of the platform 8, so as not to create an encumbrance belowit, i.e. in the space present between the platform 8 and the bottomportion of the tank 1.

The attached FIGS. 6 to 8 illustrate a further embodiment of the tankaccording to the present invention, indicated as a whole with 100.

In the following, the same reference numbers increased by a furtherhundred units will be used to indicate the components corresponding tothe previous embodiment.

The tank 100 differs from the previous embodiments in relation to thepresence of two closed paths, preferably loop-shaped, side by side,along which respective water flows are forced.

In this regard, the tank 100 includes two propulsion sections 103, 103′which are arranged on opposite sides of the swimming section 102.

More in detail, the tank 100 comprises a first separating wall 140 whichextends between the at least one first connecting section 104 and the atleast one second connecting section 105 and is configured to separatethe first propulsion section 103 from the section swimming pool 102 anda second separating wall 141 which extends between the at least onefirst connecting section 104 and the at least one second connectingsection 105 and is configured to separate the second propulsion section103′ from the swimming section 102.

In fact, the swimming section 102 is laterally delimited between thefirst grate 119, the second grate 120, the first separating wall 140 andthe second separating wall 141 and below by the platform 108.

The swimming section 102, as well as the two propulsion sections 103,103′ extend for the entire height of the tank 100, intended as adimension along the direction of movement of the platform 108.

The platform 108 is interposed between the at least one first connectingsection 104 and the at least one second connecting section 105 (see forexample FIG. 6 ).

Similarly to what has been described in relation to the previousembodiment, the tank 100 comprises a first grid 119 configured toseparate the at least one first connecting section 104 from the swimmingsection 102 and the at least one first connecting section 104 from thepropulsion section 103.

The tank 100 also includes a second grid 120 to separate the at leastone second connecting section 105 from the swimming section 102.

The tank 100 comprises members for moving the platform 108 between thelowered position, the intermediate lowered position and the raisedposition according to the methods described, by way of example, inrelation to the previous embodiment to which reference is made.

The tank 100 comprises two first connecting sections 104 and two secondconnecting sections 105 for the mutual connection between a firstpropulsion section 103 and a portion of the swimming section 102 andbetween a second propulsion section 103′ and a portion of the swimmingsection 102 (see FIG. 7 ).

In particular, it should be noted that the tank 100, in plan, has asymmetrical conformation with respect to the longitudinal developmentdirection 107.

In fact, in the tank 100 there are a first loop flow and a second ringflow which meet along the swimming section 102 with the same directionof advance (see FIG. 7 wherein the trend of each of the two flows ishighlighted by arrows).

According to a preferred embodiment, the first propulsion section 103and the second propulsion section 103′ each comprise a respectivepropeller 117 although it is understood that alternative embodimentscomprising two or more propulsion propellers 117 along each propulsionsection 103, 103′ are possible.

The tank 100 comprises a platform 108 which, in turn, is provided with afirst deflector 121 and a second deflector 122 mutually connected to theplatform 108 itself, to form a single and movable body.

In particular, the platform 108 is movable relative to the opening 106between a lowered position, wherein it defines a bottom for the swimmingsection 102, an intermediate lowered position, wherein it is spaced fromthe bottom of the tub 100 and a raised position wherein it acts byclosing for the opening 106 itself, preventing access to the swimmingsection 102 and providing a support surface that can be walked on whenthe tank 100 is not in use, in accordance with what is described inrelation to the previous embodiment, to which reference is made.

It should be noted that also the two first connecting sections 104 andthe two second connecting sections 105 are configured to eliminate orreduce as much as possible the effect of the turbulence caused by thepropulsion members along the propulsion sections 103, 103′, so to obtaina laminar or substantially laminar flow along the swimming section 102,similarly to the previous embodiment.

The person skilled in the art will easily understand how a tank 1, 100according to the invention is able to achieve the intended purposes,generating and maintaining a laminar flow at a use or swimming section2, 102.

Compared to the solutions of the known art which provide for arecirculation of the water inside the tank, to allow training in“counter-current” conditions, the tank 1, 100 according to the presentinvention allows to optimize the flow characteristics, obtaining alaminar regime along the swimming section 2, 102 as part of a solutionwith reduced dimensions and safe use.

In fact, the presence of a mobile platform 8, 108 allows you to occludeor open the opening 6, 106 of access to the swimming section 2, 102respectively to prevent or allow access to the inside of the tank 1, 100itself.

Furthermore, the possibility of moving the platform 8, 108 along theswimming section 2, 102 allows the tank 1, 100 to be used to performswimming activities in counter-current or as well as further activitiessuch as, for example, water aerobics, hydrobike or hydrorunning. Asmentioned, in fact, the platform 8, 108 can be lowered until it isbrought in correspondence with the base or substantially incorrespondence with the base of the tank 1, 100, thus acting itself as asupport surface along which to arrange the tools necessary for carryingout the aforementioned physical activities.

According to a version of the present invention, preferably with theplatform 8, 108 placed in this configuration, it is possible to activatethe propulsion members in reverse, to generate propulsion with anopposite direction (counter-current) with respect to the orientation ofany tools present inside the swimming section 2, 102, to allow theperformance of physical activity in counter-current conditions or forspecific needs of use.

In practice, the flow can be pushed starting from the propulsion section3, 103, 103′ towards the at least one second connecting section 5, 105,introduced into the swimming section 2, 102 and then introduced into theat least one first connecting section 4, 104 to then reach the at leastone propulsion section 3, 103, 103′ again.

The possible presence of a turbulent flow along the swimming section 2,102, due to the positioning of the platform 8, 108 at the base of thetank 1, 100 is not an obstacle to the performance of a physical activityof the type indicated above.

Furthermore, it is highlighted how the platform 8, 108, in addition toacting as a closing element of the tank 1, 100 or as a support surface,when arranged in the lowered position, to mutually divide the swimmingsection 2, 102 and the propulsion section 3, 103, 103′, acts as adividing diaphragm between two branches of the flow inside the tank 1,100.

In fact, the platform 8, 108 performs a triple function, albeit withinthe context of an overall simple and easy to use technical solution.

In the foregoing, the preferred embodiments have been described andvariants of the present invention have been suggested, but it is to beunderstood that those skilled in the art will be able to makemodifications and changes without thereby departing from the relativescope of protection, as defined by the claims attached.

1. A tank configured to perform physical activity in counter-currentregime comprising a swimming section, at least one propulsion sectionalong which a fluid is forced, wherein the swimming section and the atleast one propulsion section develop along a longitudinal direction, atleast a first connecting section and at least a second connectingsection for the connection, in fluid communication, of respective endsof the swimming section and the at least one propulsion section so as todefine at least one loop path along which to force the fluid, a platforminterposed between the at least a first connecting section and the atleast a second connecting section, wherein the at least one firstconnecting section comprises a plurality of first curved channels, theat least one second connecting section comprises a plurality of secondcurved channels, and wherein the platform is movable between anintermediate lowered position wherein is distal from an access openingto the swimming section and a raised position wherein it hermeticallycloses the opening preventing access to the swimming section, whereinoptionally the platform is movable in a lowered position, in abutment orsubstantially in abutment against the bottom portion of the tank to actas a support surface.
 2. The tank according to claim 1, wherein the atleast one first connecting section comprises a plurality first curvedchannels with an increasing section starting from the at least onepropulsion section towards the swimming section and wherein the at leastone second connecting section comprises a plurality of second curvedchannels with a decreasing section starting from the swimming sectiontowards the at least one propulsion section.
 3. The tank according toclaim 1, wherein the at least one first connecting section comprises aplurality of first curved walls “C-shaped” or “U-shaped”, arranged oneinside the other, mutually decentralized and with the respectiveconcavities facing towards the swimming section and the at least onepropulsion section.
 4. The tank according to claim 1, wherein the atleast one second connecting section comprises a plurality of firstcurved walls “C-shaped” or “U-shaped”, arranged one inside the other,mutually decentralized and with the respective concavities facingtowards the swimming section and the at least one propulsion section. 5.The tank according to claim 1, comprising at least one first bafflearranged at the at least one first connecting section and a secondbaffle arranged at the at least one second connecting section, whereinthe first baffle and the second baffle are configured to reduceturbulence or detachment of the flow at respective opposite ends of theplatform.
 6. The tank according to claim 1, comprising propulsionmembers configured to impart a momentum to a fluid comprised in thetank, wherein the propulsion members comprise at least one propelleroperatively connected to a motor for its operation in rotation, whereinthe at least one propeller is arranged along the at least one secondconnecting section, below the platform.
 7. The tank according to claim1, wherein the platform arranged in the intermediate lowered positiondefines a diaphragm for separating the swimming section and the at leastone propulsion section, keeping a flow which is forced along theswimming section and a flow which is forced along the at least onepropulsion section in counter-current with respect to the flow along theswimming section separated to each other.
 8. The tank according to claim5, wherein the first baffle is provided along the at least one firstconnecting section, inside a cavity delimited by a first internal curvedwall comprised in the at least one first connecting section, and thesecond baffle is arranged along the at least one second connectingsection inside a cavity delimited by a second internal curved wallcomprised in the at least one second connecting section.
 9. The tankaccording to claim 8, wherein the first baffle is connected to the firstgrid and wherein the second baffle is connected to the second grid. 10.The tank according to claim 8, wherein the first baffle has a crosssection with a decreasing shape along the longitudinal direction fromthe at least a first connecting portion to the swimming section.
 11. Thetank according to claim 8, wherein the first baffle has a cross-sectionconfigured as an ogive or drop-shaped element or a hydrodynamic elementprovided with a rounded end arranged inside the first inner curved wall,to which a descending portion which is connected to the platformfollows, along the longitudinal direction with the flow forwarddirection.
 12. The tank according to claim 5, wherein the platform, thefirst baffle and the second baffle are connected to each other to definea single body comprised along the swimming section, movable between thelowered position and the raised position.
 13. The tank according toclaim 1, comprising movement members configured to selectively move theplatform between the lowered and raised positions and intermediatepositions.
 14. The tank according to claim 13, wherein the movementmembers comprise a motor unit operatively connected to the platform bymeans of motion transmission members and guide members configured toguide the platform during its movement.